Navigate to Appearance -> Themes -> Add New -> Upload Theme. Select file. Press Upload Theme button to upload and install the theme:

You will have to activate the theme: 

After activating Milano, a quick setup wizard will be opened. It will help you to install theme required plugins, demo content, setting. Just in a few clicks your website will be ready for use.

In Bulk Actions choose Activate option and press Apply:

Read welcome message and click “Let`s go!”:

Default Plugins. Wizard will ask you to install theme required plugins. Click “Continue” and it will install and activate all required plugins.

Default Content. By clicking “Continue” setup wizard will import all demo data – pages, posts, portfolios and media files. Please note that import process will take time needed to download all attachments:

Theme customization. Here you can read information about widgets and child theme. Click “Continue”:

There is the last step – setting menu. Go to Appearance -> Menus. All you need is to click on "Top menu" and save these changes:

That’s all! Theme required plugins were installed and demo content was imported.